Risk of progression of nephropathy in a population-based sample with type 2 diabetes

AIMS

Progression through stages of nephropathy has not been well described in a large, well-characterized, population-based study. Our aims were to describe the progression of nephropathy and identify characteristics associated with progression in a U.S. population-based sample.

METHODS

We identified 10,290 members of a managed care organization who had hypertension and type 2 diabetes, a urine albumin-to-creatinine ratio (UACR) measurement in 2001-2003, and at least 2 follow-up UACRs. Progression of nephropathy was defined as progression to a higher stage of nephropathy than was present at baseline.

RESULTS

At baseline, 57% had normoalbuminuria, 31% had microalbuminuria, and 12% had macroalbuminuria. The incidence of nephropathy progression (per 1000 person-years) was 94.7, 35.1, and 6.5 for normo-, micro-, and macro-albuminuria, respectively. ACEi/ARB use ranged from 61-67%, except among patients with macroalbuminuria at follow-up. Age, diabetes duration, and A1C were significant predictors of progression.

CONCLUSIONS

Our study, one of the first to examine the progression of nephropathy in a U.S. population-based sample, showed that among adults with diabetes and hypertension, the burden of nephropathy and its progression may be greater than previously reported. Further, the use of ACEi/ARBs was not optimal.

A study of the prevalence of significant increases in serum creatinine following angiotension-converting enzyme inhibitor administration

Angiontension-converting enzyme inhibitors (ACEIs) are beneficial in the treatment of diabetic and nondiabetic kidney disease, coronary artery disease and congestive heart failure. One adverse effect of ACEIs use is a rise in serum creatinine and potential renal failure. This paper attempts to quantify this risk and assess the need for pre- and post-ACEI serum creatinine measurements. A computerized search of Kaiser Permanente Northwest's electronic medical record was conducted to find patients over the age of 40 years taking lisinopril between July 1, 2000 and June 30, 2002. Patient demographic information and presence in diabetes and coronary artery disease registries was collected. A subsequent search for pre- and postlisinopril serum creatinine levels within 6 months of initial lisinopril prescription was conducted. Patients with prelisinopril creatinine < or = 1.2 mg/dl and postlisinopril creatinine > 2.5 mg/dl underwent chart review to discern adverse events associated with the rise in serum creatinine. A total of 18,977 patients were prescribed lisinopril between July 1, 2000 and June 30, 2002. In all 13 166 patients had a pre- and postlisinopril creatinine checked. In all, 31 patients had a rise in creatinine from < or = 1.2 mg/dl to > 2.5 mg/dl (0.2%). Possible contributors to rise in creatinine included congestive heart failure, dehydration and infection. No patients developed end-stage renal disease, although three died. In conclusion, end-stage renal disease is an unlikely outcome among patients prescribed lisinopril and is most likely associated with other events.

A crossover study of gabapentin in treatment of restless legs syndrome among hemodialysis patients

Restless legs syndrome (RLS) is a common entity affecting hemodialysis patients. Although the cause of RLS remains unclear, a number of therapies have been used successfully to treat the disorder. Gabapentin is an anticonvulsant shown to alleviate symptoms of RLS in two small studies of nonhemodialysis patients. Because it is excreted renally, gabapentin has a long half-life among hemodialysis patients and may be advantageous if proven effective. We conducted a randomized, double-blind, placebo-crossover study of gabapentin in the treatment of RLS among a population of hemodialysis patients. Sixteen patients identified with RLS were randomized to either gabapentin or placebo. After 6 weeks of treatment with 200 to 300 mg of gabapentin after each hemodialysis session, patients' RLS was reassessed. After a 1-week washout period, patients were switched from gabapentin to placebo or placebo to gabapentin. After another 6 weeks, patients' RLS was assessed again. Patient data were analyzed using both parametric and nonparametric means. Thirteen of the 16 original patients completed the study. Two patients dropped out because of lethargy (believed to be secondary to gabapentin), and 1 patient died secondary to myocardial infarction. Eleven patients responded to gabapentin, but not placebo (P < 0.01). One patient responded to both, and 1 patient responded to placebo, but not gabapentin. Gabapentin is an effective treatment for RLS in hemodialysis patients.